1. Field of the Invention
The present invention relates to a rotary shelf construction and assembly and to a shelf-supporting post height adjustment device to secure the post and carried shelves in a pre-selected relationship within the cabinet along with a shelf sustaining element to enable the speedy attachment and detachment of shelves to the post.
2. Description of the Prior Art
It has been common practice to provide corner kitchen cabinet shelves of a rotatable or “Lazy Susan” type. Such shelves are desirable because, without them, much cabinet space in the corner either above or below the kitchen counter is wasted due to the inaccessibility of items well back in the corner.
One of the problems encountered with such a structure is the variance of non-uniform distances between the top and bottom of the cabinet thus requiring some accommodation for the length of the post in order for the post and shelves to fit and function properly within the cabinet.
U.S. Pat. No. 4,587,908 discloses a vertically adjustable post assembly wherein an upper post is telescoped into the upper end portion of a lower post and adjusted vertically relative thereto. Vertical adjustment is provided by an end cap attached to the upper end of the lower post by a set screw. The end cap is formed with a V-shaped key which fits into a formed channel in the upper post to prevent the upper post from rotating relative to the lower post while permitting vertical adjustment of the upper post. While the reference discloses a workable combination, it does require an end cap to slide over the upper end of the lower post thus allowing a key formed on the upper bracket to fit within the formed channel in the upper post, a combination of elements obviously more expensive than desired.
U.S. Pat. No. 4,572,595 includes an assembly having a sleeve member with first and second end portions and defining a coaxial hole therethrough. The hole slidably receives the upper end portion of the rotating support shaft, and a set screw adjustably secures the sleeve member to the rotating support shaft such that it rotates with the shaft. This fitting prevents rotational slippage, however it does not provide vertical adjustability.
U.S. Pat. No. 4,688,686 provides for post vertical adjustment through a height adjustment mechanism wherein a diamond tooth knurled cylindrical segment is rotated to threadably raise and lower the post to the desired position. A locking screw secures the vertically positioned elements in a fixed condition.
U.S. Pat. No. 4,433,885 provides vertical adjustment by means of a wedge movable horizontally against a bearing support to provide vertical adjustability.
All of these references disclose workable vertically adjustable features, however some wear excessively after frequent use. All of these adjustments are somewhat troublesome, time consuming, relatively expensive and oftentimes laborious.
In addition, some of the prior art references relating to adjusting the height of a shelf assembly require the use of special tools, and frequently the adjusting mechanisms were not easily accessible. The shelves are conventionally secured to the post in corner units like those described by the insertion of pins and other post securing attachments to permit movement of the shelf upwardly and downwardly along the post. Usually it is necessary to utilize several elements in combination to accomplish this securement thus making shelf securement rather expensive and time consuming.
Shelf construction for Lazy Susan assemblies have traditionally included the use of several separate components that were combined to form the finished shelf. Additional and separate structure was also needed to affix the shelf to the supporting post. A collar was often positioned under the shelf with a pin extending through it to engage the post and frictionally hold the collar in a stationary position and thereby support the shelf during use. Shelves made of multiple components are expensive and involve considerable time and adjustment when installed. For this reason there is a need to improve shelf structure and reduce the time normally involved in shelf installation and adjustment.